classlist_filehandling.cpp

/*
* @author : Nelmin Jay Magan Anoc
* file handling script to retrieve a simple classlist on a text file
*/


#include<iostream>
#include<fstream>
#include<string>

using std::cout;
using std::cin;
using std::string;
using std::ifstream;
using std::ofstream;
using std::endl;

const string FILE_NAME = "classlist.txt";
const string CLEAR_SCREEN = "\033[2J"; // ansi escape code for clearing a screen inside a linux terminal
const string CURSOR_UP = "\033[1;1H"; // ansi escape code for getting the cursor up on the screen

int getMenu();

void transaction(int);
void showStudents(ifstream &);
void addStudent(ofstream &);
void searchStudent(ifstream &);
void deleteStudent(ifstream &);

int main()
{

  char repeat ;

  do
  {
    cout << CURSOR_UP ;
    cout << CLEAR_SCREEN ;
    transaction(getMenu());

    cout << "Return to main menu ? (y/n): ";
    cin >> repeat ;
  }
  while(repeat == 'Y' || repeat == 'y');

  return 0;

}


void transaction(int menu_choice)
{

  ofstream class_list_of(FILE_NAME.c_str(), std::ios_base::app | std::ios_base::out);
  ifstream class_list_if(FILE_NAME.c_str());

  switch (menu_choice)
  {

    case 1 :
      addStudent(class_list_of);
    break;

    case 2 :
      showStudents(class_list_if);
    break;

    case 3 :
      searchStudent(class_list_if);
    break;

    case 4 :
      deleteStudent(class_list_if);
    break;

  }

  class_list_if.close();
  class_list_of.close();

}

int getMenu()
{

  int menu_choice = 0;

  cout << "**---------------------------------**" << endl ;
  cout << "This is a simple class set program \n" ;
  cout << "**---------------------------------**" ;
  cout << endl << endl ;

  cout << "~~choose from the menu below : \n" ;
  cout << endl ;
  cout << "(1) Add a student \n";
  cout << "(2) View student list \n";
  cout << "(3) Search student \n";
  cout << "(4) Delete student \n";

  cin>> menu_choice;

  cin.get();

  cout << endl << "~~~~end choosing from the menu~~~~" << endl ;

  return menu_choice;

}

void addStudent(ofstream &class_list)
{

  cout << CURSOR_UP ;
  cout << CLEAR_SCREEN ;

  string name_student , name_instructor ;

  cout << "~~~~add student to class list~~~~" << endl << endl ;

  cout << "Enter name of the student: ";
  getline(cin, name_student , '\n');

  cout << "Enter name of the instructor: ";
  getline(cin, name_instructor, '\n');

  class_list << name_student << " | " << name_instructor <<" \n";
  class_list.close();

  cout << endl << "~~~~end adding student to class list~~~~" << endl ;

}

void showStudents(ifstream &class_list)
{

  cout << CURSOR_UP ;
  cout << CLEAR_SCREEN ;

  string get_content ;
  string delimiter = "|";
  int student_record_counter = 0;


  cout << "~~~~showing class list~~~~" << endl << endl ;

  while(getline(class_list, get_content))
  {

      string name_student = get_content.substr(0, get_content.find(delimiter));
      string name_instructor = get_content.substr(name_student.size()+1, get_content.size());
      name_instructor.replace(name_instructor.length()-1,name_instructor.length(),"");

      cout << student_record_counter+1 << "). " << name_student << " is under " << name_instructor << endl;
      student_record_counter++;

  }

  cout << endl << "~~~~end showing class list~~~~" << endl ;

}

void deleteStudent(ifstream &class_list)
{

  cout << CURSOR_UP ;
  cout << CLEAR_SCREEN ;

  string name_student = "" ;
  string get_content = "";

  ofstream temp;
  temp.open("temp.txt");

  cout << "~~~~delete a student~~~~" << endl << endl ;
  cout << "student name : " ;
  getline(cin, name_student, '\n');

  while (getline(class_list,get_content))
   {
       if (!(get_content.find(name_student) != string::npos))
       {
           temp << get_content << endl;
       }
   }

  temp.open("temp.txt");
  remove("classlist.txt");
  rename("temp.txt","classlist.txt");

  cout << endl << "~~~~end student deletion~~~~" << endl ;


}

void searchStudent(ifstream &class_list)
{

  cout << CURSOR_UP ;
  cout << CLEAR_SCREEN ;

  string name_student = "" ;
  string name_instructor = "" ;
  string get_content = "" ;

  cout << "~~~~search a student and check if it is under an instructor~~~~" << endl << endl ;

  cout << "Student name : " ;
  getline(cin, name_student, '\n');
  cout << "Instructor name : " ;
  getline(cin, name_instructor, '\n');

  while(getline(class_list, get_content))
  {

      if(get_content.find(name_student) != string::npos)
      {

          string parse_name_student = get_content.substr(0, get_content.find("|"));
          string parse_name_instructor = get_content.substr(parse_name_student.size()+1, get_content.size());
          parse_name_instructor.erase(parse_name_instructor.begin());

          if(parse_name_instructor.find(name_instructor) != string::npos)
          {
            cout << endl << name_student << " is under " << name_instructor << endl ;
          }
          else
          {
            cout << endl << name_student << " is not under " << name_instructor << endl ;
            cout << "but under " << parse_name_instructor << endl ;
          }

      }

  }

  cout << endl << "~~~~end searching a student~~~~" << endl ;

}